Add Do Not Use a Number Line Except as a Check

Multiple Choice

Add. Do not use a number line except as a check.
- $- \frac { 3 } { 6 } + \frac { 2 } { 3 }$

A) $- \frac { 7 } { 6 }$
B) $\frac { 1 } { 6 }$
C) $\frac { 2 } { 3 }$
D) $\frac { 7 } { 6 }$